JPH01170469A - Centrifugal separation of blood - Google Patents

Abstract

PURPOSE: To enable blood cells to be returned to a patient or a supplier, by connecting a flow-out tube to a flow-in tube to circulate liquid in a separation channel to bring blood cells in a floating condition. CONSTITUTION: A disposal tubing set including a flow-in tube 12 and a disposal separation channel composes in cooperation with a pinch valve assembly a return tube valve 38, a blood plasma valve 40, taking valve 42, blood erythrocytic cell tube valve 44, and a waste liquor/flow pass switching valve assembly 39. When a centrifuge to separate a patient's blood component blood erythrocytic cells are washed off by liquid circulating in a large quantity in the separation channel. The assembly 39 is switched to the close position to open a valve 38, a flow-in pump 32 is stopped and a blood plasma pump 34 is actuated to equalize flow rates of the flow-in pump and the blood plasma pump causing to the separation channel 14 to be kept in a pressed condition and blood erythrocytic cells in a floating condition are efficiently returned.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for centrifuging blood.

[Prior Art] A centrifugal separator used to continuously separate blood components has a disposable plastic separation channel that is fitted inside a bowl (centrifuge container) that is rotated by a motor. There are some that are employed. The separation channel typically includes an inlet into which whole blood flows;
Some have two or more outlets (extraction ports) provided at different radial positions for extracting separated fractions of blood components within the separation channel. Among the separated blood components, plasma is located at the innermost position in the radial direction, and red blood cells are located at the outermost position in the radial direction. After going through a process of collecting and exchanging various components, it is returned to the body of the patient or donor along with some of the other components.

At the end of the continuous separation process, it is desirable to extract the remaining blush bulbs inside the separation channel and return them to the patient or donor. One of the traditional centrifuge systems
No. 4,094,461 (Kel
In one containing a separation channel of the general type described in Logg et al., saline is injected into the blood collection tube at the end of the run. The separation channel is collapsed by occluding the blood collection tube with a pinch valve while the pump is suctioning the return tube, and then the saline is released by releasing the occlusion with the pinch valve. It rapidly flows into the separation channel to forcefully wash away the red blood cells.

[Problems to be Solved by the Invention] However, there is room for improvement in this conventional red blood cell return method.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an improved method for returning blood components remaining in a centrifuge device to a patient or donor at the end of its operation.

[Means for Solving the Problems] In one aspect, the present invention provides a method for centrifugal separation by connecting an outflow line to an inflow line and circulating a liquid within the separation channel. After the separation, the blood cells are removed from the separation channel and returned to the patient or donor. The use of circulation increases the total flow of fluid through a given location within the separation channel to keep the cells in suspension, while at the same time increasing the dilution of the cells returned to the patient. The extent of this is considered to be small.

In another aspect, the invention generally describes a centrifugal separation channel by aspirating more liquid from the separation channel using an effluent pump than can flow into the separation channel. The collapsed state reduces the volume of fluid required to return the blood cells to the patient or donor vessel.

In a preferred embodiment, these are: circulating;
Both collapsing and collapsing the separation channels have been utilized. Additionally, prior to initiating circulation, the patient is disconnected from the inflow line and saline is pumped into the extracorporeal circuit while the centrifuge continues to separate and collect blood components. be done. The red blood cell line exiting the separation channel is flushed out, and then the red blood cell line is kept occluded while the circulation process is carried out, thereby preventing shunt flow. The separation channel is brought into a collapsed state by occlusion of the inflow conduit, and the collapsed state is then maintained by keeping the liquid source into the separation channel and the liquid outflow from the separation channel substantially the same. The separation channel is rinsed while retaining the

Other features and advantages of the invention will become apparent from the detailed description of the embodiments below.

[Example] Regarding Fig. 1, a blood centrifugation system 10 is shown in the figure, which is used to continuously separate components in blood collected from a patient via an inflow pipe (collection pipe) 12. It is shown. Separation takes place inside a disposable plastic separation channel 14 which is placed and rotated inside a bowl (not shown).

The inflow conduit 12 and the disposable separation channel 14 form part of a disposable tubing set that includes a waste collection bag 16,
Plasma collection bag 18, platelet collection bag 20, 22, inflow side (blood collection side) air chamber 24, return side (blood return side) air chamber 26, and sealless rotary multiflow tube connection assembly 28 (e.g., U.S. Pat. No. 4,146,172).

This disposable tubing set attaches to the front of a machine with multiple rollers for the force pump and multiple pinch valve assemblies. The movable pump rollers cooperate with the tubing to form an anticoagulant pump 30, an inflow pump 32, an apical plasma pump 34, and a collection pump 36. A pinch valve assembly cooperates with the tubing. The two-position return line valve (withdrawal line) valve 38 and the three-position plasma valve 40
, a three-position collection valve 42 , a two-position red blood cell line valve 44 , and a waste/flow path conversion/valve assembly 3
9, and this waste liquid/flow path diversion/valve assembly 3
9 includes a two-position waste liquid valve 41 and a three-position flow diversion valve 43; the tubing set further includes a filter/connector 46 for connecting individually supplied bagged saline 48; a filter/connector 50 for connecting the bagged anticoagulant 51 supplied to the
, and a connector 49 for connecting a physiological saline bag 53 for blood return. The tubing set further includes a plurality of manually operated pinch clamps, including a saline supply clamp 52;
There are a sampling lamp 54, a plasma sampling lamp 56, a physiological saline return clamp 55, and a sampling (2) clamp 57 and a blood return clamp 59 which are clamps for connection to the patient. (Although all manual clamps are shown in Figure 1 as having slots of decreasing width, some of these clamps may have other configurations.) Inflow line. 12 is connected to a saline supply line 58 and an anticoagulant supply line 60 from the pump 30 by a four-way connector 29 . From this connector 29, the inflow pipe 12
It is connected to the inflow side air chamber 24 via the inflow pump 32 . Further from this chamber 24, the inflow pipe 1
2 leads to a sealless connection assembly 28.

Disposable plastic separation channel 14 is a two-stage separation channel of the type described in detail in US Patent Publication No. 845,847. Other types of separation channels can also be used, such as those shown in the aforementioned KeLLogg US patent publication.

Return lines exiting separation channel 14 include red blood cell return line 66, plasma line 68, and platelet collection line 70. The red straight sphere conduit 66 is connected to the drip chamber 2 on the return side.
6 is directly connected. Plasma line 68 and platelet line 70 each branch into two branches after passing through respective pumps 34 and 36, and these branch lines pass through three-way valves 40 and 42. The three-way plasma valve 40 can be manipulated to direct flow to the plasma collection bag 18 (collection position), to the return line 72 (return position), or to both (variable positions). can. The three-position collection valve 42 similarly directs flow to the bag 20.22 (collection position), to the return line 72 (return position), or to both (variable position) by manipulating it. It can flow. Similarly, the three-way type flow path switching valve 43 allows the flow to flow into one or both of its pipes, and the two-way type (Q type valve 41) allows the flow to pass through the same valve 41. It can flow to the waste bag 16 or be shut off there.

The return saline bag 53 is connected to the return conduit 74 by a three-way connector 63.

1'' In operation, the tubing set shown in FIG. It is also connected to a physiological saline bag 53 for blood return.

Physiological saline is injected into the tubing set by a pump, thereby brimming the tubing set. The venipuncture needles connected to the inflow pipe line 12 and the return pipe line 74 are inserted into the patient or the donor, and then the blood collection side pinch clamp 57 is opened to enable blood collection from the patient or the donor. However, on the other hand, the blood return side pinch clamp 59 remains closed during the initial stage. When the collection process is started, the respective pumps are activated and the entire surface is supplied to the separation channel 14 via the inflow line 12, the separated red blood cells flow into the line 66, and the plasma flows into the line 68. Inward, the platelets flow into conduits 70, respectively. At the beginning of operation, the physiological saline inside the tubing set is eliminated by the inflowing blood and separated blood components, and the flow path is further diverted by the return side air chamber 26 and collected in the waste liquid bag 16. be done. valve 41
is used to expel saline to waste bag 16 at the beginning of donor/patient treatment, and
It is also used to exclude air from chambers 24 and 26 if necessary. Once the separated red blood cells and plasma reach the combiner 63, the waste liquid/flow path conversion/
Valve assembly 39 is closed and return line valve 38 is opened. The red blood cells and plasma are returned to the patient via line 74 and the platelets are collected into bag 20.22. During the collection process, the three-way collection valve 42 blocks flow to the return line 72 while allowing flow to the collection bag 20.22, and the plasma return valve 40 blocks flow to the return line 72. It allows flow to channel 72 while blocking flow to plasma collection bag 18. The flow within this tubing set during the collection process is shown in FIG. 1 by solid arrows.

At the end of the collection process, the red blood cells are returned to the patient using the method shown in FIG.

First, prior to step l, the operator closes the blood collection side clamp 57, removes the venipuncture needle connected to the inflow pipe (collection pipe) 12, and opens the pinch valve 52. The saline solution in the bag 48 is allowed to flow in. The operator then returns the system to automatic mode by pressing the CONT I NUE control button. As noted in Step 1, one anticoagulant pump 30 is turned on, the other pumps are activated (at appropriate flow rates), and the various valves are left in their previous states. The platelet collection process continues in this state for several minutes, during which time 60 milliliters of saline is passed through the inflow line 12 and the drip chamber 24 (volume lO ~ 15 milliliters). into the separation channel 14 (approximately 160 milliliters in volume).At this point, the operator closes and removes the collection bag 20.22 with a clamp and presses the CLEAR button.
Press the wholesale button (flow control button) to return to automatic mode.

In step 2, the centrifuge is stopped, so that the stratification inside the separation channel 14 immediately disappears. As a result, some of the red blood cells inside the separation channel 14 mix with the plasma and saline that had been separated inside the separation channel 14, and the remaining red blood cells are mixed inside the separation channel 14.
The concentrated red blood cells remain in the vicinity of the outer wall of the cell, and mainly in the region of the first stage between the inlet and the red blood cell outlet. Inflow pump 32 is activated, while plasma pump 34 and collection pump 36 are deactivated. This pump condition causes separation channel 14
All flow out of will flow through red blood cell line 66. This causes the red blood cells inside line 66 to be absorbed into line 66 (which has a very small volume) together with the approximately 90 milliliters of liquid in separation channel 14.
and the return side air chamber 26 to the return pipe 74, and at this time, 10 to 15 milliliters of liquid remains inside the return side air chamber 26. Although the volume of line 66 is small, a very high concentration of red blood cell concentrate is present inside line 66 during operation of the device. While step 3 is being carried out, the flow within the separation channel 14 is substantially short-circuited along a short path from its inlet to the red blood cell extraction port. The area between this inlet and the red blood cell extraction port contains the majority of the residual red blood cells. At the end of step 2, the fluid within line 66 contains red blood cells with a fairly low density. The volume of 90 milliliters was selected to substantially exclude all red blood cells in suspension from the separation channel 14.

In step 3, red blood cell line valve 44 and return line valve 38 are occluded, and plasma valve 40 and collection valve 42 are placed in the return position (thereby all fluid passing through these valves is removed). flow to the return circuit 72).

Additionally, the waste/flow diversion and valve assembly 39 is placed in the circulation position, with its two-position valve 41 closed and its three-position valve 43 opened. Due to the above valve conditions, the liquid follows the circulation path shown by the dotted arrow in FIG. Liquid thus flows from the inlet air chamber 24 through the conduit 12 into the separation channel 14 and through it. Furthermore, the liquid flows through this separation channel 1
4 through lines 68 and 70, pumps 34 and 36, and return circuit 72 to return air chamber 26. From there, the liquid passes through a three-way flow diversion valve 43 and returns to the inlet drip chamber 24. If the red tube conduit valve 44 were not blocked, liquid would short-circuit and flow through this valve. While this step is being performed, neither blood is drawn from the patient/donor nor blood is returned to the patient/donor. While this step 3 is being carried out, a high flow rate of 200 milliliters per minute is applied to the separation channel 14.
The circulating liquid flowing over each other for 0 seconds washes red blood cells from the walls of the separation channel. Approximately 225 milliliters of liquid is present within this closed circuit, and this liquid is therefore circulated within this channel approximately 1.33 times.

Of the 225 milliliters of volume inside this closed loop, about 100 milliliters--or more--is saline.

In step 4, the waste/flow path diversion/valve assembly 39 is switched to the closed position and the return valve (blood return valve) 38 is opened. As a result, plasma, suspended red blood cells, and physiological saline mixed with them,
Blood will now be returned to the patient/donor. Inflow pump 32
is stopped and plasma pump 34 is activated, separation channel 14 is collapsed and 1
The volume, which used to be 60 milliliters, has been reduced by about 125 milliliters to about 35 milliliters.

In step 5, inflow pump 32 is operated at 1 ffl of 50 milliliters per minute and plasma pump 34 is operated at 1 ffl of 50 milliliters per minute.
The separation channel 14 is also operated at a flow rate of 50 milliliters per minute and the flow rate is the same in one shift so that the separation channel 14 remains collapsed. Furthermore, the suspended red blood cells are returned to the patient along with plasma and mixed saline. In this step, 58 milliliters of blood is returned. The reason is that after this volume of blood is returned,
This is because most of the liquid is physiological saline.

The operator removes the return line from the patient/donor.

In this step 6, the return valve (blood return valve)
38 are automatically occluded.

1 bow There are various other embodiments that fall within the scope of the present invention.

For example, there is a method in which the collection step (step 1) is not employed and the 60 milliliters of saline that would have been used in the collection step is added to the 90 milliliters of fluid used in step 2.

[Effects of the Invention] According to the method of the present invention, when blood cells are returned to a patient or donor after blood centrifugation, it is possible to efficiently remove residual components remaining in the centrifugal separator at the end of the blood removal process. This has the effect that it can be returned to patients or blood donors in a timely manner. Further, at this time, the returned blood is not diluted significantly with physiological saline, which is convenient.

[Brief explanation of the drawing]

FIG. 1 is a fluid circuit diagram of a blood centrifugation device according to the present invention, and FIG. 2 is an automated flow diagram for returning red blood cells to a patient or donor at the end of the separation process using the device of FIG. 1. This is a chart showing the method. In the figure, 10...Blood centrifugal separator, 12...Inflow pipe, 14...Separation channel, 16...Waste liquid collection bag, 18...Raccoon plasma collection bag, 20.22- ...Dish small temporary collection bag, 24-...Inflow side drip chamber, 26...Blood return side drip chamber, 32...Inflow pump, 34...Plasma pump, 36-...Collection pump, 38. - return line valve, 40... plasma valve, 41... waste liquid valve, 42... collection valve, 43-... flow path diversion valve, 44-... red blood cell line valve, 48-... supply Physiological saline bag for use 53... Physiological saline bag for withdrawal, 66... Red blood cell line, 68... Plasma line, 70... Platelet collection line. (4 others) Spout in the drawing (no change in content) C2 Procedural Amendment CJJ February 2, 1989 Patent Application No. 205651 2, Title of the invention ゛Blood centrifugation method 3, Relationship with the case of the person making the amendment Special 2'1゛Applicant Address Name Co-op Laboratories Incorporated 4, Agent Address Shintemachi Building 206, 2-2-1 Otemachi, Chiyoda-ku, Tokyo 7. Contents of correction

Claims (11)

[Claims] (1) A method for returning blood cells to a patient or blood donor after centrifugation treatment, which comprises a separation channel for separating blood components, an inflow pipe that flows into the separation channel, and an outflow from the separation channel. a plurality of outflow conduits connecting the inflow conduit to the outflow conduit to form a closed loop; A method for keeping blood cells in suspension inside a separation channel. (2) One of the outflow conduits is a red blood cell conduit for extracting red blood cells, and further, prior to making the connection, the red blood cell conduit is flushed to eliminate red blood cells therein, and then the red blood cells are extracted. 2. The method of claim 1, further comprising occluding a red blood cell line and maintaining the red blood cell line in an occluded state during said circulation. (3) Furthermore, prior to performing the flushing, the inflow conduit is removed from the patient or blood donor and a saline supply is connected to the inflow conduit; 3. The method of claim 2, wherein before performing the flushing, the components being separated inside the separation channel are collected. (4) A method for returning blood cells to a patient or donor after centrifugation, the method comprising: a flexible separation channel for separating blood components;
providing a centrifugal separation device comprising an inflow conduit into the separation channel and a plurality of outflow conduits exiting the separation channel, and further comprising: A method in which an effluent pump is used to aspirate more liquid from the separation channel than can flow into the separation channel in order to reduce the amount of liquid. (5) While the suction is being performed, the separation channel is substantially collapsed by blocking the flow into the separation channel, and further, after that, the separation channel is brought into the collapsed state. rinsing the interior of the separation channel with a liquid while maintaining the separation channel, whereby blood cells are flushed out of the separation channel using a smaller amount of liquid due to the reduced volume of the separation channel. The method described in Section 4. (6) One of the outflow pipes is a red blood cell pipe for extracting red blood cells, and further, prior to the suction, the red blood cell pipe is flushed to eliminate the red blood cells therein, and then the red blood cells are removed. 6. The method of claim 5, further comprising occluding the red blood cell line and maintaining the red blood cell line in an occluded state during the aspiration. (7) Furthermore, prior to performing the flushing, the inflow conduit is removed from the patient or blood donor and a supply physiological saline is connected to the inflow conduit; 6. The method according to claim 5, characterized in that, before performing the flushing, the components separated inside the separation channel are collected. (8) the separation channel is flexible, further to reduce the amount of fluid required to return the blood cells to the patient or donor after performing the circulation;
2. A method as claimed in claim 1, characterized in that more liquid than can flow into the separation channel is drawn from the separation channel using an effluent pump. (9) While the suction is being performed, the separation channel is substantially collapsed by blocking the flow into the separation channel, and further, after that, the separation channel is brought into the collapsed state. rinsing the interior of the separation channel with a liquid while maintaining the separation channel, whereby blood cells are flushed out of the separation channel using a smaller amount of liquid due to the reduced volume of the separation channel. The method according to item 8. (10) the apparatus includes an inlet drip chamber and a return drip chamber, both of which chambers have a waste line joined to a waste valve; 2. The method of claim 1, comprising the step of manipulating a waste valve to allow liquid to flow from the return line drip chamber to the input line drip chamber via the waste line. . (11) The outflow pipe includes a plasma extraction pipe and a platelet collection/extraction pipe, each of the plasma extraction pipe and the platelet collection/extraction pipe branching into two branches, each of which is a branch pipe. one end is connected to a collection bag and the other end is joined at a return junction to a return conduit connected to the patient or donor, the device further controlling the flow within the bifurcated conduit. 2. The method of claim 1, further comprising a plurality of valves for controlling the return joint, wherein the step of connecting further comprises the step of manipulating the valves to allow liquid to flow through the interior of the return joint. Method described.